Penicillin Allergy De-Labelling in Elective Surgical Patients (PADLES)
Status:
Completed
Trial end date:
2017-10-02
Target enrollment:
Participant gender:
Summary
Penicillin antibiotics are safe and inexpensive, and target selected bacteria rather than
killing a broad range. Unfortunately, around 10% of the population are labelled as
'penicillin allergic'. This is often based on side effects such as rash and diarrhoea, and
90-95% of people with the label are not actually allergic to the drug.
The label leads to the use of alternative antibiotics, which tend to more toxic, and less
specific about which bacteria they kill; this increases the risk of infections with so-called
'super-bugs', compared to patients without the label. People with the label also have an
increased length of hospital stay and rates of readmission. These are significant problems
for individuals, as well as wider society. Where the diagnosis is in doubt, the gold standard
test for allergy is an oral challenge. Patients undergo skin +/- blood tests prior to a
challenge, as these can help make the diagnosis. This combined pathway is expensive and time
consuming, so testing cannot be offered routinely to all patients. However in patients with
'historic' reactions (many years previously), skin and blood tests become much less useful;
in one study, 100% of patients who skin tested positive for amoxycillin allergy, tested
negative 5 years later. Patients with historic reactions can therefore proceed directly to an
oral challenge without prior skin or blood testing, since these offer little help in making
the diagnosis. This streamlines the pathway, making it quick, non-invasive and cheap. Already
established practice in several centres in Europe and beyond, this abbreviated pathway is
offered on an ad-hoc basis in some centres in the UK.
The aim is to demonstrate that this pathway offers a safe and effective way to perform
large-scale delabelling of elective surgical patients, who might not otherwise meet NICE
criteria for testing.